Struct FileAccessRightsPersistence 

pub struct FileAccessRightsPersistence { /* private fields */ }

A file holding one Access Rights object’s written rule arrays, Enable and Accompaniment, replaced whole on each save, the same way as FileNotificationClassPersistence: a failed save leaves the previous state in place, and a completed one survives a power loss.

After the magic tag RBNACR01 and the object’s identifier, the file holds BACnet encodings of up to four members, in this order, each only once a write has set it:

• context tag 0, opening, then each Positive_Access_Rules rule in its Clause 21 BACnetAccessRule encoding, then context tag 0, closing;
• the same for Negative_Access_Rules under context tag 1;
• Enable as a context-tagged BOOLEAN with tag 2;
• context tag 3, opening, then Accompaniment in its Clause 21 BACnetDeviceObjectReference encoding, then context tag 3, closing.

Loading refuses a file past 128 KiB, an array of more than MAX_ACCESS_RULES rules, members out of order or repeated, a rule or reference that does not decode, and octets after the last member. It does not check the rules or the reference themselves; the object does, as it loads them. It does not coordinate between processes.

Implementations

impl FileAccessRightsPersistence

pub fn new(path: impl AsRef<Path>) -> Result<Self, Error>

Keep the rule arrays, Enable and Accompaniment in the file at path.

pub fn path(&self) -> &Path

The file the rule arrays, Enable and Accompaniment are kept in.

Trait Implementations

impl AccessRightsPersistence for FileAccessRightsPersistence

fn load( &self, rights: ObjectIdentifier, ) -> Result<Option<AccessRightsSnapshot>, Error>

What was last saved for rights, or None when nothing was saved.

fn save( &self, rights: ObjectIdentifier, snapshot: &AccessRightsSnapshot, ) -> Result<(), Error>

Durably replace what is saved for rights with snapshot.

impl Clone for FileAccessRightsPersistence

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FileAccessRightsPersistence

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.